For the last year, research for this project number was carried out under new project number Z01 BN02020-01 LIM (Oxidants and cell death). Hence, we have no new results for this project. However, we are now initiating a new series of studies designed to determine how protein oxidation might play a role in cell death. Specifically, experiments will be carried out to assess mitochondrial protein oxidation during chemotherapy induced apoptosis and H2O2 induced cell death. Mitochondrial function is central to the apoptotic process and there are several key mitochondrial proteins which are particularly susceptible to oxidative modification. We will look to see whether these proteins are modified during cell death and will determine whether this oxidation has any effect on cell death pathways. Other subcellular fractions will also be tested (e.g., plasma membrane, nuclear, and cytosolic fractions). The target cells for these studies will be human lymphoma and breast cancer cells.